/**
 * @author mrdoob / http://mrdoob.com/
 */

THREE.SphereGeometry = function ( radius, widthSegments, heightSegments, phiStart, phiLength, thetaStart, thetaLength ) {

	console.log( 'THREE.SphereGeometry: Consider using THREE.SphereBufferGeometry for lower memory footprint.' );

	THREE.Geometry.call( this );

	this.type = 'SphereGeometry';

	this.parameters = {
		radius: radius,
		widthSegments: widthSegments,
		heightSegments: heightSegments,
		phiStart: phiStart,
		phiLength: phiLength,
		thetaStart: thetaStart,
		thetaLength: thetaLength
	};

	radius = radius || 50;

	widthSegments = Math.max( 2, Math.floor( widthSegments ) || 8 );
	heightSegments = Math.max( 2, Math.floor( heightSegments ) || 6 );

	phiStart = phiStart !== undefined ? phiStart : 0;
	phiLength = phiLength !== undefined ? phiLength : Math.PI * 2;

	thetaStart = thetaStart !== undefined ? thetaStart : 0;
	thetaLength = thetaLength !== undefined ? thetaLength : Math.PI;

	var x, y, vertices = [], uvs = [];

	for ( y = 0; y <= heightSegments; y ++ ) {

		var verticesRow = [];
		var uvsRow = [];

		for ( x = 0; x <= widthSegments; x ++ ) {

			var u = x / widthSegments;
			var v = y / heightSegments;

			var vertex = new THREE.Vector3();
			vertex.x = - radius * Math.cos( phiStart + u * phiLength ) * Math.sin( thetaStart + v * thetaLength );
			vertex.y = radius * Math.cos( thetaStart + v * thetaLength );
			vertex.z = radius * Math.sin( phiStart + u * phiLength ) * Math.sin( thetaStart + v * thetaLength );

			this.vertices.push( vertex );

			verticesRow.push( this.vertices.length - 1 );
			uvsRow.push( new THREE.Vector2( u, 1 - v ) );

		}

		vertices.push( verticesRow );
		uvs.push( uvsRow );

	}

	for ( y = 0; y < heightSegments; y ++ ) {

		for ( x = 0; x < widthSegments; x ++ ) {

			var v1 = vertices[ y ][ x + 1 ];
			var v2 = vertices[ y ][ x ];
			var v3 = vertices[ y + 1 ][ x ];
			var v4 = vertices[ y + 1 ][ x + 1 ];

			var n1 = this.vertices[ v1 ].clone().normalize();
			var n2 = this.vertices[ v2 ].clone().normalize();
			var n3 = this.vertices[ v3 ].clone().normalize();
			var n4 = this.vertices[ v4 ].clone().normalize();

			var uv1 = uvs[ y ][ x + 1 ].clone();
			var uv2 = uvs[ y ][ x ].clone();
			var uv3 = uvs[ y + 1 ][ x ].clone();
			var uv4 = uvs[ y + 1 ][ x + 1 ].clone();

			if ( Math.abs( this.vertices[ v1 ].y ) === radius ) {

				uv1.x = ( uv1.x + uv2.x ) / 2;
				this.faces.push( new THREE.Face3( v1, v3, v4, [ n1, n3, n4 ] ) );
				this.faceVertexUvs[ 0 ].push( [ uv1, uv3, uv4 ] );

			} else if ( Math.abs( this.vertices[ v3 ].y ) === radius ) {

				uv3.x = ( uv3.x + uv4.x ) / 2;
				this.faces.push( new THREE.Face3( v1, v2, v3, [ n1, n2, n3 ] ) );
				this.faceVertexUvs[ 0 ].push( [ uv1, uv2, uv3 ] );

			} else {

				this.faces.push( new THREE.Face3( v1, v2, v4, [ n1, n2, n4 ] ) );
				this.faceVertexUvs[ 0 ].push( [ uv1, uv2, uv4 ] );

				this.faces.push( new THREE.Face3( v2, v3, v4, [ n2.clone(), n3, n4.clone() ] ) );
				this.faceVertexUvs[ 0 ].push( [ uv2.clone(), uv3, uv4.clone() ] );

			}

		}

	}

	this.computeFaceNormals();

	this.boundingSphere = new THREE.Sphere( new THREE.Vector3(), radius );

};

THREE.SphereGeometry.prototype = Object.create( THREE.Geometry.prototype );
THREE.SphereGeometry.prototype.constructor = THREE.SphereGeometry;